Many individuals are troubled by premature baldness, receding hairlines, or other conditions in which hair is lost from the head. Over the years, a variety of chemicals have been marketed as hair regrowth aids but with mixed, generally disappointing results. Many individuals have invested considerable sums in artificial hair pieces. Some individuals have even undergone surgical hair implantation procedures requiring the exercise of highly skilled medical expertise which is generally unavailable to a wide cross-section of potential beneficiaries. It will thus be appreciated that there is a need for a reasonably inexpensive hair regrowth process capable of being administered by relatively unskilled personnel and capable of promoting hair regrowth in the widest possible population cross-section.
The prior art discloses that a variety of electrical stimuli have been employed in an effort to promote hair growth. For example, U.S. Pat. No. 861,349 issued Jul. 30, 1907 for an invention of R. E. Beaubien entitled "Apparatus for Treating the Scalp" discloses an "apparatus for promoting the growth of hair upon the human head". The apparatus appears to rely upon a combination of pneumatic, vacuum and electrical effects, in combination with the application of medicated lotions and massage to the scalp. According to Beaubien, any desirable form of electrical battery or current may be used. The present applicant however believes that this is not the case and that in order to satisfactorily promote hair regrowth, specific electrical signals must be employed.
U.S. Pat. No. 735,581 issued Aug. 4, 1903 for an invention of Pollacsek, et al. entitled "Therapeutical Apparatus" discloses a device "by means of which vibrations of diseased parts of the body can be produced". Pollacsek, et al. indicate that the device may be shaped as a cap to be placed on the head and that the cap may be introduced into a magnetic field produced by an electric current passing through the windings of an iron core. However, there is no indication of the specific nature of the electric or magnetic signals or fields employed, nor is there any suggestion that Pollacsek, et al. considered applying their device to promote hair regrowth.
U.S. Pat. No. 740,385 issued Oct. 6, 1903 for an invention of W. B. Bassell entitled "Electrotherapeutic Appliance" provides another device "adapted to subject the wearer to the action of a current of electricity for curative purposes". Bassell explains that his invention is to be utilized for the relief and cure of nervousness, insomnia, headache, and other kindred troubles. He suggests that this may be accomplished by subjecting the head of the wearer to the action of a comparatively mild current of electricity provided by a small battery. Again however there is no suggestion that Bassell considered the use of his device to promote hair regrowth, nor are any specific electrical signals discussed.
U.S. Pat. No. 3,872,859 issued Mar. 25, 1975 for an invention of Pitzen, et al. entitled "Method and Device for Stimulating the Organs Associated with the Human Scalp" examines the problem of promoting hair growth in some detail. Pitzen, et al. provide a method and apparatus in which a plurality of wave form generators output signals having frequencies varying from 230 hertz through 2650 hertz. The waveform generators are also pulsed at repetition rates varying from 3 times per second to 26 times per second. The signals so produced are applied to hand-held massaging electrodes which are in turn applied to the subject's scalp.
Published French patent application No. 2,484,262 of Paul Maurice Viallis provides another electrical apparatus and method for treating the human scalp to combat seborrhoea, hair loss, dandruff, etc. A conductive electrode cap is fitted over the scalp and a secondary electrode is placed in contact with another area of the body. A current of the order of 8-15 mA is applied for a period of 5 to 30 minutes depending upon the type of complaint and type of treatment prescribed. The object of Viallis' invention is apparently to ionize the scalp area so that ointments or other applied treatment compositions may penetrate the scalp with greater effectiveness.
Published West German patent application No. 3,618,933 discloses an invention of Masaki, et al. pertaining to an electrotherapeutic device for promoting eyebrow hair growth. The apparatus is shaped to fit on a patient's head. Electrodes are applied to the eyebrows. A pulse-like current preferably having a square or trapezoid waveform is applied to the electrodes, with a biphasic action, potential-like oscillation having a frequency in the 1/500 to 1/200 second range and pulsed at a frequency of 0.5 to 2 seconds is preferably applied to the electrodes.
Two published British patent application Nos. 2,160,426A and 2,160,427A of Masaki appear to correspond to the West German application aforesaid, although the British applications do not appear to restrict themselves to eyebrow hair growth.
U.S. Pat. No. 3,946,745 Hsiang-Lai et al teaches a system in which electrical pulses are applied directly to a living body, for example by attaching electrodes to the body by means of an acupuncture needle or spring-loaded earring.
German patent application DE 29 52 850 A1 teaches the use of electromagnetic pulsating fields for stimulating the body functions furthering the growth of hair. Frequencies in the 400-420 hertz range are mentioned, with the subject undergoing continuous exposure to the fields, for example by having the subject carry a battery powered apparatus on his/her person.
French patent No. 1,350,890 teaches a hair dryer having an electrode structure to which a high frequency voltage generator is electrically coupled in order to apply an intense high frequency electric field to the hair so as to heat and evaporate water from the hair. The patent mentions that the applied field also has a stimulating effect on the cells of the skin and improves blood circulation, which is favourable to the metabolism and to healthy growth of hair.
Although not wishing to be bound by any theory, the inventors believe that dormant body hair cells (i.e. hair cells from which hair is not actively growing) may be electrically stimulated to promote active hair growth from such cells. More particularly, the inventors believe that hair regrowth can be promoted if the body's hair cells are stimulated by subjecting them to a low voltage pulse train having a pulse repetition frequency in the range of about 5 to 35 hertz. The higher portion of this frequency range is considered appropriate for subjects who exhibit normal or hyperactive energy levels. The lower portion of the frequency range is considered appropriate for individuals who exhibit hypoactive or slow metabolism energy levels.